Variable speed ribbon winding machine



Aug. 23, 1966 .1. GUICHON ET AL 3,268,380

VARIABLE SPEED RIBBON WINDING MACHINE 19 Shecs-Sheet 1 Filed Jan. 30, 1963 N mN Aug. 23, 1966 L. J. GUICHON ET AL 3,268,380

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VARIABLE SPEED RIBBON WINDING MACHINE Filed Jan. 30, 1963 19 Sheets-Sheet 5 INVENTORY.- 1401 0 60/67/04/ Aug. 23, 1966 L. J. GUICHON ET AL 3,268,380

VARIABLE SPEED RIBBON WINDING MACHINE Filed Jan. 30, 1963 19 Sheets-Sheet 4 prroew:%

Aug. 23, 1966 GUICHON ET AL 3,268,380

VARIABLE SPEED RIBBON WINDING MACHINE Filed Jan. 50. 1963 19 Sheets-Sheet 5 INVENTORJ'. 4401 0 J: au/awa/v /(//CHOZ4I z Mar:

Aug. 23, 1966 .1. GUICHON ET 3,268,380

VARIABLE SPEED RIBBON WINDING MACHINE l9 Sheets-Sheet 6 Filed Jan. 30. 1963 IN VEN TORI Ava/044! 17 m1: 5 j 204 flf/OZA/ZM Aug. 23, 1966 sump- N ET AL 3,268,380

VARIABLE SPEED RIBBON WINDING MACHINE Filed Jan. 30, 1963 19 Sheets-Sheet 9 Ail 23, 1966 1.. J. GUICHON ET AL 3,268,380

VARIABLE SPEED RIBBON WINDING MACHINE l9 Sheets-Sheet 10 Filed Jan. 30. 1963 INVENTORJ'. J 60/6/90 /U/(f/Oiif Z V046! 7 477020474 Adm 0 Aug. 23, 1966 J, GulcHoN ET AL 3,268,380

VARIABLE SPEED RIBBON WINDING MACHINE Filed Jan. 30, 1963 19 Sheets-Sheet 12 aawr Aug. 23, 1966 J GUlCHON ET AL 3,268,380

VARIABLE SPEED RIBBON WINDING MACHINE Filed Jan. 30, 1963 19 Sheets-Sheet 13 XXXXXXXXXXX 7372 L13 7 6 prraex/az 19 Sheets-Sheet 14 Aug. 23, 1966 GUlcHON ET AL VARIABLE SPEED RIBBON WINDING MACHINE Filed Jan. 50, 1963 Aug. 23, 1966 L. J. GUICHON ET AL VARIABLE SPEED RIBBON WINDING MACHINE Filed Jan. 30, 1963 19 Sheets-Sheet l5 INVENTORJ. ZlOVO J' 60/6346 Aug. 23, 1966 J. GUICHON E AL 3,268,380

VARIABLE SPEED RIBBON WINDING MACHINE 19 Sheets-Sheet 16 Filed Jan. 50. 1963 L. J GUICHON ET AL VARIABLE SPEED RIBBON WINDING MACHINE Filed Jan. 30, 1963 lllll.

Sheets-Sheet 18 I NVEN TORI.

,. 3,268,380 Patented August 23, 1966 3,268,380 VARIABLE SPEED RIBBON WINDING MACHINE Lloyd J. Guichon and Nicholas T. Volsk, Costa Mesa,

Califi, assignors to W. J. Voit Rubber Corp., a corporation of California Filed Jan. 30, 1963, Ser. No. 254,958 18 Claims. (Cl. 156-130) This invention relates to machines and methods for winding an elastomeric material on a casing of a pneumatic vehicular tire in the course of its original manufacture or for retreading used pneumatic tires.

The invention will be described in connection with the retreading of used tires first, and it then will be followed with the description of applying elastomeric material to a casing of a new tire in the course of its original manufacture.

According to this invention, a relatively thin ribbon of natural or synthetic rubber, or a combination of the two, or other elastomeric material, extruded by a local extruder, which constitutes a part of the machine, is wound at a predetermined and controllable rate of azimuth movement on the pneumatic tire casing which has been previously properly buffed and coated with cement. At the beginning of the automatic winding process, the free end of the locally extruded, hot, tacky and very pliable ribbon, which has a temperature between 150 F and 250 F., depending on the composition, upon its extrusion, is manually secured by adhesion to a sidewall of the casing at a point located along one edge of the layer to be deposited on the casing. This is the only manual step in the process. From then on the winding is continued under the control of an electronic programmer until a predictable and the desired variable thickness layer of uncured elastomer has been automatically applied to the bufied surface of the tire. The variable thickness layer is obtained by winding, as it will be called here, a variable pitch continuous spiral on the casing. The nature of this variable pitch continuous spiral will become more apparent from a later, more detailed description of the two types of spirals which may be produced with two distinct methods of winding the ribbon on tire casings disclosed here.

According to the first method, the continuous spiral consists of several sets of constant pitch spirals which are obtained by subdividing the casing or the width of the contemplated variable thickness layer to be deposited on the casing into a plurality of sectors and making the pitch of the spiral constant within each sector, thus producing a single, continuous variable pitch spiral composed of a plurality of constant pitch spirals within each sector. The magnitude of each pitch within each individual sector is adjusted so as to produce or deposit the desired thickness of the elastomer within each sector. Even in the above method, the pitch remains constant within a given sector only as long as the thickness of the extruded ribbon remains constant.

According to the second method, the pitch of the spiral remains constant only as long as the desired thickness of the layer remains constant and the thickness of the extruded ribbon remains constant. There is no subdivision of the width of the layer into a plurality of sectors since the programmer of the machine is controlled by a variable amplitude, or height, cam, which may have very many variations in its amplitude. This cam corresponds to the desired thickness of the layer.

The above two distinct methods are applicable to the new and used tires and to variable thickness layers with or without beauty rings. Moreover, the beauty rings may be desired along or at the two edges of the layer in retreading old or used casings, and it may be desired approximately in the middle of each sidewall sector or portion of the layer when making new tires.

The disclosed variations in the programmers, which make all of the above methods possible, include all of the above alternatives.

Let us describe more in detail the first method, using several sectors, as it applies to a used tire with two beauty rings at the two edges of the layer. Such spiral begins with one to three turns having a zero pitch at which time either one, two or three complete turns of ribbon are superimposed on top of each other for producing the so-called beauty ring, and then it is followed by a spiral, the pitch of the spiral being automatically changed several times by decreasing and increasing the pitch several times and, in this manner, by varying the percentage of overlap between 100% at the beauty rings and a minimum overlap of 5% at the sidewalls, in the course of the winding cycle at predetermined positions of the ribbon on the casing. Such changes in the pitch of the spiral and the percentage of overlap, and the angle of inclination of the ribbons face to the surface of the casing are obtained automatically with the aid of the electronic programmer, the machine, in this manner, depositing a variable thickness layer of the elastomer on top of the casing. The winding cycle is then completed, just prior to its termination, by winding again one, two or three turns having zero pitch, i.e., one, two or three complete turns which are 100% superimposed on top of each other in order to produce the second beauty ring at the second sidewall of the casing. Thus, the entire ribbon winding cycle is completed during a single transverse path, or pass, of the ribbon across a casing as differentiated from a plurality of paths and a plurality of passes and a plurality of superimposed layers of the ribbon known to the prior art. The wound pattern, therefore, begins and ends with a desired number of turns, from one to three turns, which has or have zero pitch. These zero pitch turns are used for obtaining the so-called two beauty rings which project beyond their respective sidewalls and protect these sidewalls from scuffing, usually against curbstones, when parking. Between the two beauty rings there is a plurality of sets of constant pitch spirals, the first set followed by the second set, etc. As will be pointed out more in detail later, there are five sets of essentially constant pitch spirals in the illustratedexample: two sets for two sidewalls, two sets for two shoulders and one set for the crown. These five sets were found to be sufficient to obtain the type of variable thickness layer desired for retreading used tires and, with some modifications, for making new tires. In this manner, a variable thickness single elastomeric layer of uncured elastomeric ribbon is deposited along the outer surface and periphery of the casing. This layer fills completely and exactly the space, or gap, between the inner surface of the matrix and the outer buffed surface of the casing. It is well known in the art of retreading and also in making of new tires, that the casing and the external elastomeric layer must engage the matrix in the mold for obtaining proper adhesion of the elastomer and elimination of any air pockets in the subsequent compression molding.

Upon completing of the winding cycle, the casing is compression molded in conventional manner to produce a tread of proper depth, resurfaced sidewalls, and beauty rings, when such are desired, all positively bonded to the casing.

The locally extruded ribbon thus not only eliminates the necessity of having large stocks of composite tread rubber, having a natural rubber adhesion underlayer of different sizes and different compositions required by the present methods, but it also drastically reduces the initial cost of the elastomer because of the elimination of all prior special size extrusions, elimination of the natural rubber adhesion underlayer, expensive polyethylene backing, special packing in individual boxes, enormous amounts of clerical paper work, writing and sorting of 

1. A METHOD OF DEPOSITING A VARIABLE THICKNESS ELASTOMERIC LAYER ALONG AN OUTER PERIPHERY OF A TIRE CASING DURING A SINGLE OPERATING CYCLE, SAID METHOD INCLUDING THE STEPS OF LOCALLY EXTRUDING A FLAT ELASTOMERIC RIBBON HAVING A WIDTH GREATER THAN THE MAXIMUM THICKNESS OF SAID LAYER, APPLYING THE FREE END OF SAID RIBBON TO A POINT ALONG ONE EDGE OF SAID LAYER, THEREAFTER SPINNING SAID CASING AROUND ITS SPIN AXIS AND SIMULTANEOUSLY MOVING AT A VARIABLE RATE SAID CASING IN THE DIRECTION OF SAID SPIN AXIS TO MAKE SAID RIBBON FOLLOW A PATH OF A VARIABLE PITCH SPIRAL, GENERATING A VARIABLE MAGNITUDE SIGNAL DURNAL IN SYNCHRONISM WITH AND TO THE EXTENT SO AS TO MAKE SAID SIGNAL REPRESENT THE DESIRED THICKNESS OF SIAD LAYER AT ANY GIVEN INSTANT OF SAID CYCLE, AND CONTROLLING SAID RATE OF TRANSVERSE MOVEMENT WITH THE AID OF SAID SIGNAL TO MAKE SAID RIBBON FOLLOW SAID VARIABLE PITCH SIGNAL.
 8. AN AUTOMATIC CONTROL SYSTEM FOR A RIBBON-WINDING MACHINE FOR DEPOSITING A VARIABLE THICKNESS ELASTOMERIC LAYER BY WINDING AN ELASTOMERIC RIBBON ALONG AN OUTER SURFACE OF A PNEUMATIC TIRE CASING, SAID SYSTEM INCLUDING A SOURCE OF SAID ELASTOMERIC RIBBON, FIRST MEANS FOR SPINNING SAID CASING AROUND ITS SPIN AXIS, FIRST CONTROL MEANS 